Category:Corydoras

While there are hundreds of catfish available to the aquarist today, only a few are suitable for the casual hobbyist. Almost all of these are cory cats - fish in the genus Corydoras. These little, armoured catfish, mostly from South America, are comical, attractive, peaceful, and easy to keep.

As with most Corydoras, these fish will eat most food which sinks to the bottom of the tank. Sinking algae pellets should be supplemented with flake food or other sinking foods like catfish pellets.

Be aware these fish do have a carnivorous side to them and love foods such as Bloodworm and Brine Shrimp. Vegetable-based foods offer little nutrition to them. They will also eat any dead, dying, or even injured fish, that sit on the substrate too long. They're very opportunistic!

Requires a sand or small gravel substrate and prefers a planted tank. Keeping a cory on sharp or large gravel can lead to damage to their barbels, which when infected will make it hard for the cory to find food.

Corys are sensitive to salt, as with other scaleless fish, adding salt to the tank will cause them harm.

The Corydoras group of fish frequently gulps air. This is normal and is not a cause for concern. If too little room is available between the water surface and the hood (<2") the fish may hit the hood. They hold the air in their stomach and the thin lining dissipates the oxygen.

This fish likes the company of its own kind. It is recommended to keep at least 2, or better yet, several of the same species. The more you have, the more secure they are and the more you will see them.

They are known to 'blink' their eyes to the amazement of onlookers. The Cory has the ability to tilt its eye down to examine the nearby substrate.

In these fish the posterior intestine is modified to function as an air breathing organ by being air-filled, thin-walled and highly vascularized. This means the fish often comes to the surface to swallow gulps of air and passes this to its rear intestine to supplement its oxygen intake via its gills.

The male will try to get his body in front of the female whilst she is on the substrate. He positions himself midway across her head in a classic 'T' shape with his anal opening against her mouth.

If the female is interested the female attaches her mouth to the male's genital opening and directly drinks his sperm. The sperm pass through her intestine and are discharged together with eggs into the ‘pouch’ formed by her pelvic fins. [1]

Many species of Corydoras have a poisonous self-defence mechanism against being eaten by much larger fish. All Corys have very sharp fin spines and some seem to give off a low level toxic chemical into the water when frightened or highly stressed.[2] This toxin is believed to be only mildly irritating to people and only if the person is stressing and handling the Cory with their bare hands and is stung.[3][4]